Drone aircraft like this one will someday be used by law enforcement agencies in Vermont, according to a lawmaker who wants a law in place regulating them.

MONTPELIER — At a hearing late last month on Capitol Hill, Sen. Patrick Leahy spotlighted a powerful technology on which policymakers are only beginning to turn their focus.

The same kinds of drones used to track America’s enemies abroad, Leahy said, are now flying over in U.S. airspace. And while the remotely controlled devices may offer new benefits, he said, their use “raises serious concerns about the impact on the constitutional and privacy rights of American citizens.”

“I am convinced that the domestic use of drones to conduct surveillance and collect other information will have a broad and significant impact on the everyday lives of millions of Americans going forward,” said Leahy, chairman of the Senate Judiciary Committee.

The Democrat isn’t the only Vermont politician who wants to scrutinize the use of unmanned surveillance on domestic targets. A Hartford lawmaker will bring the issue to the local stage later this month when he introduces legislation that would regulate the use of drones by law enforcement agencies in Vermont.

Rep. Kevin “Coach” Christie says the bill would require police to secure a search warrant before using unmanned aircraft to monitor citizens. He says the legislation at its core is designed to start a conversation in Montpelier about a tool that could soon enter the inventories of state and local police departments.

“A constituent raised the issue with me at Town Meeting Day, and I went home and did some Googling,” he says. “And it seems to me this is something we might want to get a handle on sooner rather than later.”

Commissioner of Public Safety Keith Flynn says his department doesn’t have any drones, nor does it use other entities’ drones to conduct investigations. Asked whether the Department of Homeland Security or other federal agencies are using drones in Vermont airspace, Flynn says he’s never had a conversation with them on the subject.

“We don’t have any drones, and I don’t have any immediate plans to get any,” Flynn says.

Allen Gilbert, executive director of the Vermont chapter of the American Civil Liberties Union, says the apparent absence of drones in Vermont shouldn’t diminish the urgency of legislation like Christie’s.

“We don’t know of any verified sightings, or even the use of a drone in Vermont, other than by hobbyists,” Gilbert says. “But these things will be flying over us I’m guessing within a year. And just like any technology that has all sorts of possible uses, over time the temptation to take advantage of all those possible uses will be so strong that it will be irresistible.”

Gilbert says drones are capable of reading license plate numbers from as high as 10,000 feet, allowing agents of the state to monitor crowds, track individuals’ movements or scope out backyards for marijuana plants without the subjects ever knowing they’re being watched.

The Border Patrol already flies drones over portions of the U.S. borders with Mexico and Canada. And the use of federal drones for law enforcement investigations isn’t without precedent. In 2011, local police borrowed a U.S. drone to stamp out a cattle-rustling operation in North Dakota.

“Without checks on the use of the technology, Vermonters’ privacy really is threatened,” Gilbert says.

Christie says he doesn’t want to impede legitimate and constitutionally benign uses of drones, which he says could offer real benefits to the state. But he says the state should establish clear guidelines in advance of their arrival.

Vermont won’t be the only state to consider state-based legislation regulating the use of drones. The Virginia Legislature earlier this year passed a bill prohibiting drones from entering the state’s airspace. Virginia Gov. Bob McDonnell amended he bill to allow for life-saving operations.

Florida, Kansas, Maine and Rhode Island all have pending legislation. And lawmakers in New Hampshire late last month tabled a bill that would have prohibited drones from capturing pictures of citizens, or launching attacks on them.

Flynn says he’ll have to see Christie’s bill before he can pass judgment on its merits. But he says any new technology, like the automated license plate readers with which lawmakers are grappling now, demands policies dictating conditions of their use.

“The bigger issue is how we as a state want to deal with new tools as they come about,” Flynn says. “And that’s part of a bigger conversation.”

As for whether he anticipates the arrival of drones in Vermont anytime soon, Flynn says he always has to at least consider the pros and cons of emerging law enforcement technologies.